Orthotic caliper

Abstract

An orthotic caliper having at least two lockable steels for attachment to the respective limb members of the human body and having a locking pivotal connection between the steels, characterized by a releasable locking member which can be loaded in compression by the steels and which acts directly on at least one of the steels, and preferably on both of them, to lock them in a desired position when so loaded.

I claim: 
     
       1. An orthotic caliper having at least two steels for attachment to two respective limb members of the human body, pivotal connection means connecting the two steels together so as to form a pivotal joint between the steels, the pivotal connection means thereby allowing the steels to rotate with respect to each other so as to permit the steels to take up a variety of angular positions with respect to each other, a releasable locking member arranged to abut and thereby act directly on at least one of the steels to lock the steels in a predetermined desired position against rotational movement in both directions relative to each other, said desired position being selected from the variety of relative positions which the steels are able to take up, and means on the steels which act on the locking member to apply compressive forces to said member when the steels are locked in said desired position, said compressive forces serving to hold the locking member in its locking position, and the releasable locking member being free to move, as the steels are brought into said desired position, in order to abut the said surface on said one steel. 
     
     
       2. An orthotic caliper according to claim 1, wherein a gap is provided between opposed end surfaces on the two steels, and wherein the locking member is a wedge provided with surfaces adapted to abut corresponding surfaces on the steels. 
     
     
       3. An orthotic caliper according to claim 2, wherein the wedge frictionally engages said corresponding surfaces on the steels to hold the wedge in position by friction while the wedge is under load. 
     
     
       4. An orthotic caliper according to claim 2 or claim 3, wherein the surfaces of the steels on which the wedge abuts are flat surfaces machined directly on to or into the steels so that a slot is formed into which the locking wedge fits tightly. 
     
     
       5. An orthotic caliper according to claim 1, wherein the pivotal connection means between the two steels comprises two spaced-apart pivot points so that the joint has dual pivots. 
     
     
       6. An orthotic caliper according to claim 2, wherein the wedge has a rod which is provided at the end remote from the wedge with a plunger or piston movable within a cylindrical chamber. 
     
     
       7. An orthotic caliper according to claim 6, wherein the plunger or piston projects outwardly from the cylindrical chamber so as to serve as a push-button in order to release the caliper from its locked position. 
     
     
       8. An orthotic caliper according to claim 1, wherein spring means are provided to urge the locking member into a locking position.